1. Field
The following description relates to a coil assembly that may be used for wireless charging.
2. Description of Related Art
In order to charge secondary batteries that are disposed inside electronic devices such as smart phones and other portable terminals, a system of wireless power transmission and reception may be used.
A wireless charger generally includes a power transmitter that transmits power, and a power receiver that wirelessly receives power and stores the received power.
Most wireless chargers transmit and receive power using electromagnetic induction or resonance. To this end, a coil is provided in each of the power transmitter and the power receiver of a wireless charger to serve as a transmitter coil or a resonant receiver coil.
According to a related art, a circuit pattern forming method is used to form a coil pattern on a substrate. However, in this case, a thickness or a width of the coil pattern may be limited, and thereby the coil pattern may exhibit excessively high resistance loss.
Further, when a plurality of coil patterns are formed on a single substrate, it becomes difficult to lead a terminal to the outside of the coil, thereby increasing manufacturing cost.